Monday, December 9, 2013

A Cautionary Rant about "Aggregate Throughput"

I cringe when I hear, "aggregate bandwidth" or "aggregate throughput" as it's commonly used by radio marketeers. To me it's madly misleading, and so I take offense when a salesperson uses it on me, though I know they're just following convention.

By "aggregate" throughput, the vendor is taking the transmission rates (potential) from both directions and adding them together. It's as though someone asks you how much you can bench press and you say 300 pounds because you can lift 150 pounds up and then back down. Or that you can jump six feet because in your three foot leap, you come down three as well.

I've been selling bandwidth since leaving college in the 80's, and since the first Ethernet radios (FCC licensed) made it on the market, speeds have always been quoted as full-duplex, the assumption being that you're getting the same performance from the other end as well. Isn't that the way you order phone lines or fiber?

But 802.11 radios at 2.4 GHz (and later 5.x GHz) were quite slower than FCC licensed ones, largely owing to all the software overhead, and after they made the scene some marketing genius decided that 24 Mbps didn't sound "robust" enough and so he called it a 48 Mbps "aggregate" rate. I wish that all other vendors had declined to follow suit, but they caved because no one wants to appear to have a slower product.

All the while, FCC licensed radios (true "carrier-class" radios), have continued to quote the actual full-duplex data rate (since the 1980's) and I hope that never changes. The main buyers of those radios are sophisticated telecom operations - along with larger enterprise users, and they wouldn't put up with crazy-ass throughput representations. Nor, now should you.

As a PS: "Aggregate bandwidth" is of course not the same as when you take feeds from multiple radios (or fiber, etc.) and combine them in your switch. That way of talking about "aggregate" throughput makes all the sense in the world. 

#aggregatebandwidth #microwavebandwidth #rfbandwidth #wirelessthroughput #wirelesswan